Dividing a wetland landscape into hydrogeomorphic units by using a hydrogeomorphic delineation approach: a case study in Tram Chim National Park, Vietnam

Abstract

Wetlands account for about 41% of the total global ecosystem services value; therefore, they preserve a role as the most precious ecosystems on Earth. However, 35% of global wetland areas have been lost since 1970 as many wetlands have been exploited unsustainably. In this context, a hydrogeomorphic delineation approach has been developed to divide a wetland landscape into units which have homogeneous hydrological regime, geomorphology, and soil, named as hydrogeomorphic units (HGMUs). These units are fundamental units of a wetland for functional and resilience assessment of a wetland in different uses; then, to determine optimal management strategies for maintaining its complete ecosystem functions. This study used Tram Chim National Park for applying the hydrogeomorphic delineation approach for breaking a landscape of the park down into HGMUs. The findings showed that the park may be divided as three classes, including depression, riverine, and flat. Each class continued to be subdivided as subclasses. The results showed that there were six subclasses, i.e. six HGMUs, which identified in the park. Based on the results, the study described characteristics of HGMUs and created maps of HGMUs distribution of the park. These results will be a basis for next steps of applying functional assessment procedures for analyzing potential of the HGMUs to perform ecosystem functions in our upcoming study for preservation and management purposes in Tram Chim National Park.